In a far-off corner of the land of Ilnacia, siblings Velk and Thiana run an underground slave market.
One rainy night, a customer arrives with an unusual request: for the two to take a girl into their care for six months.
Offered a large sum, Thiana accepts without a second thought. But great danger looms on the horizon...

Capella's Promise is a JRPG made by PlainSoft in RPG Maker VX Ace. It has a main plot about 20 to 30 hours long with optional sidequests and many other gameplay features, including:

The Specialize system, where SP won from battles can be used to level up Specialties and learn moves or passive skills.
An item synthesis system, where you can use raw materials to create anything you have the recipe for.
Fully-randomized equipment dropped by enemies, as well as fixed equipment from shops and the like.
A fortification system of embedding Orbs into equipment to grant it additional properties and stat boosts.

Collections with Capella's Promise